MySQL Logger Replication Files

I have noticed that my zimbra folder is quite large lately. All but a few users are using the POP3 protocol. I discovered that it wasn't because of the message store, but rather the logger database. I had a quick look at the database, but it is only a hundred megabytes or so. I went digging into the directory structure and found that there are over a hundred MySQL Replicaton Log files. There are approximatley 9GB worth of these files. Does this sound like a probable size, and is there a way to clean them up?